CU division and PC prediction mode selection method and system in HEVC frame

Abstract

The invention discloses a CU division and PC prediction mode selection method and system in an HEVC frame. The method comprises steps that coding mode to-be-selected CTU are successively extracted; aprediction angle in a 180-DEG frame is divided into 8 texture direction ranges, the histogram statistics method is utilized in combination with the superimposable characteristic of a histogram to acquire texture direction range-amplitude distribution histograms under different CU sizes, and the corresponding optimal texture direction range, texture intensity and texture complexity; whether a CU block is divided is determined according to texture complexity of the CU block; a candidate mode list is determined according to texture intensity of a PU block, the optimal texture direction range of the PU block and a prediction mode of a neighboring PU block; the rate distortion cost of candidate modes is calculated, and the mode with the lowest rate distortion cost is selected as the optimal prediction mode for the PU blocks. The method is advantaged in that computational complexity is significantly reduced, the PU optimal prediction mode is rapidly selected, and the method can be widely applied to the video coding field.

Description

technical field [0001] The present invention relates to the field of video coding, in particular to a method and system for CU division and PU prediction mode selection in an HEVC frame. Background technique [0002] Digital video compression coding technology has developed rapidly. Since the 1990s, it has been a research hotspot at home and abroad. Its main goal is to pursue the highest possible coding efficiency on the basis of the same video reconstruction quality within a certain computing resource. . The High Efficiency Video Coding (HEVC) standard is the latest generation of international video coding standards, and compared with the previous generation coding standard H.264 / AVC, it achieves a bit rate reduction of about 50%. [0003] For intra prediction, HEVC supports flexible coding unit sizes from 64×64 to 4×4 and up to 35 prediction modes, including 33 directional prediction modes, DC mode and planar mode, making HEVC intra prediction The complexity is higher th...

AI Technical Summary

Problems solved by technology

[0017] 1) Unreasonable use of texture superposition and texture complexity under different CU sizes to divide CUs (according to depth), and the amount of calculation needs to be further reduced;

[0018] 2) The number of candidate mode lists for the PU prediction mode is still large, resulting in slow selection of the optimal PU prediction mode

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